MOSCOW, July 15 (UPI) — Two firefighters were killed Thursday in a blaze at a historic Moscow center for the restoration of art work.

A senior fire official told RIA Novosti that dozens of firefighters extinguished the blaze at the Grabar All-Russian Art, Scientific and Restoration Center. Three helicopters were also dispatched to attack the fire from the air.

The cause was believed to be a blowtorch being used by construction workers doing repairs to the two-story building, ITAR-TASS said.

The center was founded in 1918 by Igor Grabar, a member of a wealthy Russian family who had become an artist and art historian. Grabar, who headed the center until 1930, was a prominent member of the Soviet art establishment until his death in 1960 at 89.

Fire officials said most of the art works at the center were rescued, but some on the top floor might have been destroyed.

The center has recently been involved in the restoration of frescoes in Moscow churches and conservation of important icons.